package main

import (
	"fmt"
)

func add(a int) int {
	return a + a
}

func substract(a int) int {
	return a - a
}

func main() {
	operations := map[string]func(int)int {
		"add" : add,
		"substract" : substract,
	}

	fmt.Println(operations["add"](20))
	fmt.Println(operations["substract"](10))
}
